How You Can Leave Your Car Running to Charge Battery

How You Can Leave Your Car Running to Charge Battery

Last updated on January 13th, 2023 at 08:26 pm

If you live in a city or town where you do not get to use your vehicle regularly, then there is every possibility that your battery will shut down.

Many people who rarely drive their cars because they the need does not arise usually experience this problem.

If your car battery has never been dead, then you must drive the car most of the times. Leaving your vehicle for up to a month will kill its battery.

The power of your car might also affect the battery and make it dead in two weeks. This is because some vehicle needs power to survive.

The electrical system of a car works in such a way that the battery is charged by the car. A car battery is built in such a way that it provides enough electricity to charge the car.

This helps the engine to start running. Once the engine starts running, it will not stop unless there is an issue with it or it runs out of fuel.

The engine and the serpentine belt are connected and when the engine turns, the belt will power other components of the vehicle.

One of these components is the alternator. The alternator is responsible for charging the battery of every car. It is one of the most important parts of a car as it provides the battery with electricity.

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    One of the main causes, why the battery of a vehicle will shut down, is if it has not been charged for a long time or it is dead.

     If you have a car that you use regularly, then the probability of it going off is really slim. With proper maintenance or care, the battery will last for a long time.

    Sometimes, it might happen that a car is left for a long time due to circumstances.

    Now, if you have not driven your vehicle lately and you do not want any problem with its engine, there are ways to do that. What you can do is leave the engine running in the garage or in front of your house.

    Even if you do not move the car from one location to another, as long as the engine is running, the battery will gain needed electricity.

    You need to keep the engine running for as long as possible if you want to keep the battery charged. This is because a flat battery needs about 2 hours to charge up to 80%.

    To be sure your battery is charging while the engine is running, you should check it with a voltmeter. Ensure the alternator is working fine and will provide the battery with needed charge. Cars are not supposed to be left parked in the garage for a long time. They are meant to be driven around. Leaving it for a long time will affect its battery.

    How long can a car battery last without the engine on

    How long a battery can last without running the vehicle’s engine depends solely on the kind of car. Some can last up to a month while other batteries will be flat in two weeks.

    You can park your vehicle for a month before it runs out. Cars that have lots of power can last for two weeks before the battery runs out.

    Components of vehicles like Mercedes nd BMW need constant power to survive. So, if their engines are neglected for two weeks, the battery will go flat.

    It is advisable to remove your cars battery if you are planning of neglecting the car for few weeks. You should remove it and keep it in a safer environment.

    Ensure you protect the battery from moisture if you plan on detaching it from the car. Once it is removed, you will need to recharge it every 12 weeks to avoid a dead battery.

    Whether the battery remains in a car or not, you need to keep it charged. Cars are not built to be left sitting for a long time.

    How long to idle car to charge battery

    The component responsible for charging the car battery is the alternator. Before the alternator charges the battery, the engine needs to be running.

    So, even if your vehicle is in idle, the engine needs to be running to charge the battery. As long as the alternator can provide the needed volt of electricity to the battery, it will get charged.

    If the battery of the car is dead, it will take a long time for it to get charged. This is because the battery will need lots of current since it is discharged.

    It might require about 60 amps or even higher to get charged. If you charge a battery that is flat for two hours, it might get to 80%. For this to be achieved, the alternator needs to have about 14 volts at the terminals while the battery is charging.

    As a car owner, you need to know that cars should not be kept at idle. They are made to be driven around.


    In conclusion, sometimes it might be unavoidable to neglect your car for a long time. There are times in a person’s life where they will not really need to drive around.

    What you can do to avoid a dead battery is to get a smart charger. With a smart charger, you will be able to keep your battery charged just as it needs.

    All you have to do is plug it and it will do its work.  If you cannot afford a smart charger, then you should look for time you would run the engine and take it for a drive. Cars are machines that should not be left alone for a long time. They need to be up and running.

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