How Long Should I Let My Car Idle to Charge Its Battery? – Right Time for Your Car

One of the more common questions people have when it comes to batteries is how long they should let their car idle to charge. After all, if your battery is low and you need to get somewhere quickly, wouldn’t it be better to just start the engine? There are two main reasons you might want to let your car idle while it charges:

First, it will charge more quickly this way. Second, if you do start the engine, you run the risk of knocking out your battery’s protection and causing it to fail. In general, you should allow your car to idle for about two hours to charge. However, there are a few exceptions to this rule. If you have a high-powered charger or your battery is particularly old or weak, allow it to idle for up to four hours.

If you’re looking for useful info about charging your car’s battery, you’re in the right place. You don’t have to waste time trying to figure out this task on your own. With our help, you can learn all about it in less than 10 minutes!

Knowing how to charge your car battery properly will help you avoid making mistakes along the way. This is important because making certain mistakes can end up damaging your battery and your car, which is something everyone wants to avoid. That’s why we provide you with essential info you should get acquainted with to charge your battery in the safest and most practical way! Let’s start learning.

Charging Systems

There is no definitive answer to this question, as it depends on the type of battery, the charger, and other factors. In general, however, experts recommend letting a car idle for around two hours to fully charge it. Conversely, if a car’s battery is flat, it may be best to recharge it as quickly as possible using a standard charger.

How a Battery Works

It works very simply. An electric current flows through the lead and acid solution, creating chemical reactions that produce energy. This energy is stored in the battery until you need it when it is released to power your car or another device.

How Long Should My Car Be Idle To Charge the Battery?

While some would advise leaving your car idling to recharge the battery, this is not generally advised. Older cars may be restarted by idling for 15 to 20 minutes. However, this practice is not necessarily beneficial for your car.

There are mechanisms in place in modern automobiles that will increase the battery life. The ability of your automobile to charge at low RPMs is similarly restricted by these technologies, so unless you are moving faster, idling will only slightly charge your battery.

Your car may experience issues if it idles for too long. Your engine can end up being unprotected because the oil in the automobile will become contaminated more quickly. A lot of mishaps can occur, and they can cause quite an inconvenience for you. These issues can end up leading to component failure.

If you’re often in a rush and on a tight schedule, having your car battery die is likely the last thing you would need. However, even if such a scenario occurs, the important thing is that you know exactly how much time it will take for your battery to kick off again.

The truth is, it won’t take an eternity for your battery to charge, even after taking into account the fact that it is dead. Because it has been discharged, the battery will require a lot of electricity. 60 amps or more, preferably.

In all likelihood, a flat battery can be charged to 80% in 2 hours. However, in order for this to be feasible, the alternator must continuously maintain 14 volts at the battery terminals. It’s crucial for people to understand that automobiles are not designed to sit idle. They should be driven around.

Your car will charge at neutral as long as the alternator and the engine are in excellent condition. If you’re wondering whether your car charges while driving, the answer is yes— this is the easiest method to charge your battery. The battery will fully recharge the more you drive the automobile. When the automobile is being driven, the many parts that depend on the battery perform at their peak.

Is My Alternator Charging the Battery at Idle?

You’re probably curious whether your alternator will be charging the battery while your car is idling. The answer is yes, the alternator in your automobile will be able to charge the battery, but it must meet two requirements:

• There must be engine power (even at idle, the engine runs)
• The alternator has to be in good functioning condition

The alternator is essentially moved by the engine’s serpentine belt. The automobile battery is currently charged by the alternator. Even though the belt spins more quickly when the car is moving, the alternator’s output is controlled by the vehicle’s electronic control unit (ECU) and always provides the same voltage whether the vehicle is moving or idling. But if you want the battery to properly recharge, you should take the car for a drive occasionally. The battery’s life will be significantly lengthened as a result.

The Effects of idling

The average car battery will last around 500 to 600 charge and discharge cycles before it requires replacement. This means that if your car is parked for an hour with the engine off, the battery will be discharged by around 20%. Discharging it excessively can lead to reduced battery life, acid corrosion, and even prematurely wearing out the electrical system in your car.

When parking your car with the engine off, limit how long you leave it idle. Try to keep your car sitting in one spot for no more than two hours at a time. If you need to leave it in a parking lot longer than that, turn off the engine every 30 minutes or so so that the battery doesn’t get too low on power.

Could I Charge My Battery by Revving the Engine?

Yes, your battery will usually charge when you rev your engine, but not always. The car’s system makes sure the battery is charged at all times. However, you will need to crank the engine to generate some charge for batteries that are substantially drained.

Because there is a higher amperage when the engine is revved, the battery may charge more quickly. Continuous revving will use more fuel and energy, increasing consumption. Even while it occasionally may be beneficial, we do not recommend doing this on a regular basis because revving your automobile might harm the engine.

If done over a lengthy period of time, revving can generate sudden temperature swings that stress the engine’s parts and result in costly damages.

When to Charge Your Car

There is no one answer to this question as charging times will vary depending on the make and model of your car, battery type, climate conditions, and power outlet.

However, general guidelines suggest that most cars can be charged within two hours by connecting the electric vehicle’s charger to a standard 120-volt household outlet. For faster charging, some electric vehicles come with higher voltage chargers that can provide up to 240 volts.

Charging Systems and How to Choose One

Charging systems vary significantly in how long they’ll take to charge a battery, so it’s important to choose the right one for your needs. The three main charging types are direct current (DC), alternating current (AC), and rapid discharge.

  • AC chargers are the most common type and work by plugging into an outlet. They take about 3 hours to charge from 0% to 100%.
  • DC ones are the fastest type, but they require a special adapter and can only be used with batteries that have a DC connector. They take about 30 minutes to charge from 0% to 100%.
  • Rapid discharge is a hybrid between AC and DC. They have both AC and DC ports, so you can use them with either type of battery. They take about 1 hour to charge from 0% to 100%.

How Do I Know If My Battery Is Being Charged?

If you aren’t sure whether you’re battery is being charged, you can use a voltmeter to check. That way, you’ll know whether it’s being charged or not right away. We provide you with a list of useful information when it comes to charging your battery—check it out below:

• The positive side of the battery should be linked to the red end of the lead, and the negative end to the black lead
• A reading of around 12.6 volts is what you should be obtaining
• You may start the car and measure the voltage at the battery terminals. If it is between 14 and 15 volts, the alternator is operating normally, and you don’t need to get a new battery

An average battery lasts for five years. Your battery might need to be replaced if it has exceeded the threshold limit.

What Should You Do if Your Battery Dies Mid Road

If your car battery dies on the road, there are a few things you should do to keep yourself safe. If your car has a manual transmission, disengage the clutch and put it in neutral. You can then start the engine by turning the key to “on” but don’t start driving yet! Put your hazard lights on and wait for help. If your car has an automatic transmission, hold down the brake pedal and turn the key to “off.” Then try starting the car by turning it on with the key.

Read our article on do power inverters damage car batteries so you can be informed not to damage yours.


It’s always a good idea to leave your car battery charged, but how long should you let it idle to do so? There is no definitive answer to this question since each vehicle and charging system is different.

However, a general guideline is that you should allow your car battery to idle for at least two hours every day in order to keep the cells fully charged. This will help ensure that your car starts up easily and runs smoothly when you need it most.

Follow the tips we provided in this article and you won’t have to worry about a thing the next time you find yourself in need to charge your battery—you’ll be able to do it in record time and with minimum effort!


How Long Should you Let Car Idle to Charge Its Battery faq

1. How long will a new car battery last?

New ones usually last for about 3 years or 3000 miles. If you are experiencing frequent battery problems, it is best to get a new one as soon as possible.

2. How do I know if I need a new car battery?

There are a few things you can do to check if you need a new one. The first is to check its condition by looking at the battery icon in the system tray. The icon will show you its health and whether or not it needs to be replaced. If the icon is yellow, then it means that it needs to be replaced.

3. I have a car, what do I need to know about car batteries?

A car battery is an important part of your car. It helps start the engine and keeps the car running. Make sure to replace it every 3 years, depending on how much you use your car.

4. How do I charge a car battery?

You can charge it by using a standard charger. Follow the manufacturer’s instructions to make sure that the charger is compatible with it.