How long to charge a dead car battery

The same batteries could be charged in about 12 hours 16 hours and 24 hours with a 4-amp charge respectively. That means it will take a longer period to recharge.

The most common rate for car battery chargers is around 4 amps.

How long to charge a dead car battery. It takes between 4 to 24 hours to fully charge a totally dead car battery depending on how many Amperes your car battery charger is charging with and your car batterys size. The most common rate for car battery chargers is around 4 amps. It is quite difficult to figure out the charging time of a dead car battery.

Dead car battery means it is highly discharged. That means it will take a longer period to recharge. A car battery normally takes 8 hours for 100 charging.

But if it severely discharged then that charging time can extend up to 12-14 hours. Plug in charger - Plug the charger in and follow the manufacturers recommendations on how to charge the battery. Most chargers will do this automatically.

If yours is not automatic make sure that you start off with a slow charge at approximately 2 amps. You can do this for about an hour before raising the charging amperage. At least 30 minutes of driving will help charge the battery back to a safe level for your next start.

Below 12 Volts Use a Dedicated Charger Your vehicles alternator can keep a healthy battery charged but it was never designed to completely recharge a dead car battery if the unit in question reads below 12 volts. Depending on the age of your battery the capacity and construction of the charger and the charging technique used it may take a few hours to reach a complete charge. However always be prepared to leave the charger on overnight in case it takes longer than expected.

Realistically speaking a flat battery can be charged up to 80 percent in 2 hours. But to make this possible the alternator has to manage 14 volts at the battery terminals the whole time it is being charged. It is also important for people to realize that cars are not meant to be kept idle.

From dead fully discharged it would take a small car battery about 25 hours a larger car or small SUV battery 32 hours or a larger SUV and Truck about 48 hours to fully charge on a 2-amp charge. The same batteries could be charged in about 12 hours 16 hours and 24 hours with a 4-amp charge respectively. Let the dead battery charge for a few minutes and then turn the ignition on the vehicle of the dead battery to see if it starts.

If it doesnt the battery might need to be replaced. The length of time it takes to charge your car battery is completely dependent on the size or amp of your battery and the amp of the car charger you are using. If using a low amp charger it can take up to 24 hours to charge your battery properly but a high amperage charger such as a 40 amp charger will get the job done adequately in an hour or less and will get you on the road again in only a few minutes.

So a 2 amp charger will deliver 2 amp per hour to this flat battery and if it requires 48 amps that in means it needs 24 hours to fully charge. A 10 amp charger in comparison will take a little under five hours to fully charge the 48 amp battery. How to charge a car battery depends on how dead the battery is.

Its important to know just how dead your cars battery is before you decide how to recharge it. A healthy battery will show 124 to 127 volts across both terminals when measured with a voltmeter a handy device for diagnosing battery issues. It will take around 24 hours to charge a dead battery at this load fully.

There is another way to bring your dead batteries back to 100 of their original working condition. EZ Reconditioning Battery Method of Tom Ericson. Many battery chargers deliver two to six amps some allow you to choose the amperage level and will take at least several hours to recharge a dead car battery.

Read the instructions that come with. Nevertheless do not fast charge the battery if you will leave the car unattended. As for the slow charge it is ideal for a battery that has been dead for a long time.

Luckily you can leave the car battery on slow charge even the entire night. Check whether the car battery works after charging. Let the dead battery charge for a few minutes.

If the dead vehicle wont start after five minutes your battery probably needs to be replaced. Its very important to drive around for at least 15 minutes to fully charge your battery again. Voltage reading should fall as the car tops off the battery the time it takes depends on battery state of charge about five to ten minutes is normal Turning on lights and other consumers should cause the voltage to rise immediately as the alternator reacts to the extra electrical demands Common alternator problems include.

If you let your vehicle idle for about 20-30 minutes depends on how many RPMs your engine idles at that should return enough charge to restart later without trouble. To fully recharge take it for a spin for about an hour and try not to use the radio DVD lights or anything else that draws electricity. Charge it back up.

A common reason for a dead car battery is that its been drained by the lights being left on without the engine running. If your battery hasnt completely discharged you may be able to charge it using a car battery charger that plugs into the mains. We sell a range of these so keep one in your garage and youll always be.