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## How long does it take to charge a car battery at 1.25 amps?

80 Ah / 1.25 A = 64 Hours, so a nearly constant 1.25 amp charger (that would be the Battery Tender^{®} Plus) takes only 64 hours to return 80% of the charge to a 100 Ah battery that was fully discharged.

## How long does a 5 amp charger take to charge a battery?

A charger with 15 amps, for instance, will take about two hours to fully charge a battery at a 25-percent discharge value. Chargers with only 5 amps, however, will need a full six hours with the same battery.

## Can a 1.25 amp charger charge a car battery?

It can be used to recharge, however at 1.25 amps it could take quite a while on a car/boat battery. Used primarily to “condition” a battery and hold it at full charge. … Use a standard charger which generally charge at 6-10 amps.

## How long does it take a 1 Amp charger to charge a car battery?

If you’re using a 1-amp charger and your battery is completely dead (0 amps), it will take 48 hours. However, if you’re using a 2-amp charger, it will take 24 hours. Each amp that the manufacturer rates the charger for will restore one amp in the battery per hour.

## How do I know when my car battery is fully charged?

A fully charged battery will typically display a voltmeter reading of about 12.6 to 12.8 volts. If your voltmeter is showing a voltage anywhere between 12.4 and 12.8, that means your battery is in good shape. Any voltage above 12.9 volts is a good indicator that your battery has excessive voltage.

## How long should you leave a car running to charge the battery?

Be sure to drive your car for about 30 minutes before stopping again so the battery can continue to charge. Otherwise, you might need another jump start.

## How long does a 4 amp battery charger take?

How Long To Charge A Car Battery At 4 amps? Normally, a deep cycle battery often holds 48 amps so if you charge it at 1 amp, it will take you 48 hours. Similarly, if you charge your car battery at 4 amps, the total time to make the battery fully charged is about 12 hours.

## How long does a 6 amp charger take to charge a car battery?

Using a 6 amp charger on a 48 amp battery takes 8 hours to charge from empty. The charger puts out 6 amps an hour and has to work for 8 hours to reach 48 amps.

## How fast does an alternator charge a battery?

A: Charging time depends on the battery and the charger. For a battery being charged by the car’s alternator it can take an hour of driving to get it fully charged. Car batteries range from 40AH to 110AH, and alternators range from 45 amps to 200 amps.

## How many amps should my battery maintainer be?

For general use, any battery charger, or trickle charger, that puts out between about 1 and 3 amps will do, and you don’t really need one with float mode monitoring unless you want to be able to leave it connected for some reason.

## Can a trickle charger ruin a battery?

Leaving a battery connected to a trickle charger for too long can lead to overcharging, causing damage to the battery. … Although they can’t recharge a dead battery, they can be used frequently and left connected to a battery without any risk of overcharging.

## Can a trickle charger revive a dead battery?

You can’t “resurect” a dead battery with a trickle charger. A trickle charger is meant to maintain a fully charged battery. Bring the battery inside for 24 hours then put it back in, drive around for an hour and have the electrolytes checked at your trusted local repair shop.

## Is it safe to charge car battery overnight?

It is not safe to charge your car battery overnight as it damages the battery. Replacing a damaged battery will cost you significantly. To avoid all these extra costs, follow your battery manufacturer on the car battery’s usage and maintenance. Select the correct charger for your car battery.

## What happens if you leave a car battery charger on too long?

A: If you leave the charger connected continuously, even at a mere 2 amps, the battery eventually will die. Overcharging a battery causes excessive gassing — the electrolyte gets hot and both hydrogen and oxygen gas are generated. … On sealed batteries, the buildup of gases could cause the battery to burst.

## How many amps do you need to start a car?

400 to 600 amps will be more than enough to jump-start any normal, consumer vehicle. Commercial vehicles may require up to 1500 or 2000 amps. Compact and small vehicles can be boosted with as little as 150 amps.